Floor sanding machine



May 27, 1952 J. E. SWALINKAVICH JR FLOOR SANDING MACHINE Filed April 2. 1949 5 Sheets-Sheet l y 1952 J. E. SWALINKAVICH, JR 2,598,080

FLOOR SANDING MACHINE Filed April 2. 1949 5 Sheets-Sheet 5 y 1952 J. E. SWALJNKAVICH, JR 2,598,080

FLOOR SANDING MACHINE 5 Sheets-Sheet 4 Filed April 2, 1949 lmuan'o Ev Joseph 6. sue/m law-CA, Jr,

17 M 4/. wwm

May 27, 1952 J. E. SWALJNKAVICH, JR 2,598,080

FLOOR SANDING MACHINE 5 Sheets-Sheet 5 Filed April 2. 1949 r 0 t n o v n se all. \sualinkwi k Patented May 27, 1952 UNITED STATES PATENT OFFICE FLOOR SANDING MACHINE Joseph E. Swalinlravich, J r., Robbinsdale, Minn.

Application April 2, 1949, Serial No. 85,157

My present invention relates to improvements in floor sanding machines.

An object of this invention is to provide an endless abrading belt that runs under a worksupported drum and over an upper driven roll of different diameters, whereby the work-engaging area of the belt passing under the drum is constantly changing its circumferential relation to the periphery of the drum during each cycle of the belt.

Further objects and advantages of this invention are that the abrading belt has a continuous and unbroken abrading surface and in which the belt is given steady and uninterrupted pull, without chatter; that produces an even and smooth sanded surface throughout the full width of the belt.

A further object of this invention is to provide such an abrading belt that has an extremely large abrading area resulting in long life; that wears evenly throughout its entire width and length, whereby the entire abrading surface has the same sharpness as the same wears down; that has a relatively long cooling period from the time it leaves the drum until its return; that tends to materially reduce the gumming of the belt and the loading of the interstices in the abrading material with resulting friction; and that flexing of the long upwardly moving run of the abrading belt loosens and discharges dust and other matter in said interstices.

A still further object of the invention is to provide a floor sanding machine having a section that is removable from the main body of the machine without disturbing any of the parts thereof or their adjustments.

Other objects of the invention will be apparent from the following description, reference being had to the drawings.

To the above end, generally stated, the invention consists of the novel devices and combination of devices hereinafter described and defined in the claims.

In the accompanying drawings, which illustrate the invention, like characters indicate like parts throughout the several views.

Referring to the. drawings:

Fig. 1 is a right-hand side elevational view of the improved sanding machine;

Fig. 2 is a left-hand side elevational view of the same;

Fig. 3 is a view corresponding to Fig. 2, with the exception that some parts are broken away and other parts are shown in central vertical section;

Fig. 4 is a view partly in elevation and partly in section taken on the line 4-4 of Fig. 3;

Fig. 5 is a fragmentary detail view partly in plan and partly in section taken on the irregular line 55 of Fi 2;

Fig. 6 is a plan view of the improved sanding machine;

Fig. '7 is a fragmentary detail view partly in elevation and partly in section taken on the line l! of Fig. 1, on an enlarged scale;

Fig. 8 is a fragmentary detail view partly in elevation and partly in section taken on the irregular line 8-8 of Fig. 7;

Fig. 9 is a view corresponding to Fig. 2, with the exception that certain parts are broken away and other parts are sectioned on the line 9-9 of Fig.

Fig. 10 is a fragmentary view in rear elevation of the frame and the combined motor bed and driven r011 assembly mount;

Fig. 11 is a fragmentary detail view partly in elevation and partly in section taken on the line lI-ll of Fig. 9;

Fig. 12 is a fragmentary detail view partly in plan and partly in section taken on the line l2'-I2 of Fig. 7; and

Fig. 13 is a rear end view of the suction fan housing and attached motor, some parts being broken away and other parts sectioned.

The improved sanding machine includes a housing l3 for an abrading belt and associated parts, as will presently appear. This housing I3 is rearwardly inclined and the top H thereof is semicircular from front to rear. The front member l5 and the rear member 15 of the housing l3 are tangential to the top l4 and in slightly downwardly diverging relation. The bottom of the housing l3 is open and in its side member I1 is a wide aperture 13 at the transverse center thereof. This aperture l8 extends through the open bottom of the housing l3 and nearly to the top thereof. The other side member IQ of the housing l3 has in its upper half an aperture 20 similar to the corresponding part of the aperture I8. Both upper ends of the apertures l8 and 20 are semicircular and concentric to the housing top l4.

As an integral part of the housing l3, at the back thereof, is a dust scoop chamber 2| having a back member 22, a bottom member 23, that is downwardly and forwardly inclined to the bottom of the housing 13, and side members 24. This chamber 2 I, at its top and front, is open to t e in r orniih us g "at his a here:j

of. In the back member 22 is a large annular dust escape hole 25.

The improved sanding machine further includes a frame 26 having two side members 21 and 28, the former being secured to the rear member I5 of the housing I3 by screws 29. This side member 21 is in the plane of the housing side member 11 and projects rearwardly therefrom. That portion of the side member 28, rearwardly of the housing I3, is identical with the side member 21 and the front portion thereof extends to the front of said housing. The side member 28 is spaced outwardly of the housing l3 to leave a narrow compartment 39 therebetween. Integral with the front end of the side member 28 is a front member 3| that contacts said housing andhas the same contour as its front member I5, except its upper end portion which curves inwardly. Spacing lugs 32, integral with side member 28, engage the housing side members [9 and are secured thereto by screws 33;

Wheel housings 34 are formed in the rear. end portions of the side. members 21 and 29 by insetting the same. A pair of axial floor wheels 35 in the wheel housings 34 arejournaled to the sides thereof. The side members 21 and 23, at their rear end portions, are connected and'held laterally spaced by a hinge rod 36'. This hinge rod 36 has shoulders 31 that impinge the inner sides of the side members 2l-and 28 and washers and cap nuts 38' are applied to the outer end portions of said hinge rod.

A flat motor bed 39 extends upwardlyand forwardly between the frame side members 21 and 28. Integral with the rear end of the motor bed i 39 and'the righthand side thereof are depending flanges 49 and 4|, respectively, the former having, at its end portions, a pair of depending cars 42. These ears 42 are detachably secured by screws 43 to hubs 44 on the hinge rod 36 and support the motor bed 39 for limited vertical swinging movement. Collars 45 on the hinge rod 36 hold the hubs 44 with a working fit between the side members 21 and 28 and said collars. The motor bed 39, at its front end, is spaced from the housing [3 to leave a passageway 46 therebetween. An electric motor 41 is mounted on the motor bed 39, with its armature shaft 48 extending transversely thereof. The motor 41 is secured to its bed 39 by nut-equipped studs 49 anchored to said bed and extendingv through slots 50 in the base 5| of the motor 41.

The motor bed 39 has a long narrow forwardly projecting extension that affords a mount 52 for driven roll assembly that is integral with the left-hand side portion of the bed and overlies the compartment 39. Integral with the left-hand side of the motor bed 39 and the mount 52 is a depending flange 53 and integral with the front end of the bed 39 and the flange 53 is a front member 5A closely positioned to the upper endof the front member 3|- The flanges 4| and 53 extend between the frameside members 21 and 28' and have a close working fit therewith. The mount 52, the flange 53 and the front member 5 3 afford a top closure for the compartment 39. A

transverse channel 55 is formed in the mount 52.

and its flange 53 at the front member 54.

The mount-52 carries a driven roll assembly 55 that extends through theaperture-20 and transversely through the housing 13. This assembly 56 includes a cradle 51, the left-hand end portion of which extends through the channel 55 in the mount 52 and has on its sides trunnions 58 mounted in the sides of said channel and sup-' porting said cradle for hinge-like movement in the plane of the housing IS. The end of the cradle 51, outwardly of the channel 55, affords an integral bearing 59 in the form of a flat plate. The outer end of the cradle 5! aifords a bearing 62 in the aperture 18. This bearing 62 is also in the form of a flat plate detachably secured by screws 93 to the body of the cradle 51.

On the under side of the cradle 51 is a pair of axially aligned rollers 64 and 55- that rest on cams 66 and 61, respectively. The roller 64 is turnably mounted on a pin 68 secured, at its end portions, in the flange 53 and a depending ear 69'on the under side of the cradle 51 at its transverse center. The roller is turnably mounted on a pin 10 secured at its end portions to the prongs of a yoke-like bearing bracket 1! provided with an upstanding screw stud 12 having threaded engagement with a boss 13 on the under side of the cradle 51 at its outer end. A look not 14 on the screw stud 12 impinges the cradle 51. The cradle 51 further includes a reinforcing rib 15 on its under side and transverse center. A driven roll 16 in the housing l3 has on one of its end portions integral twin V pulleys 11 that are between the housing side member H- and the bearing 59-. Trunnions 18 on the roll 16 and the outer pulley 11 are mounted in the bearings 62 and 59, respectively. A pair of matched V belts 19 run over the V pulleys 11 and V pulleys Won the armature shaft 48 of the motor 41.

A guard BI is provided for the belts 19' and includes a side member 82 and'a cover member 83 that is integral with the ends and top of said sidemember. The side member 32- is in the plane of the frame side member 28 and its lower portion overlaps the motor bed '39 and the mount 52. The belt guard 9|, at its front, is detachably secured to the mount 52 by screws 89 and to the rear end portion. of the motor bed 39 by screws 85; The cover member 83 of the belt guard 8|, at its inner edge portion, engages the respective side of the housing 13. The side member 82 of the belt guard 8| has an opening 85 in which the bearing 59 fits. The tops of the bearings 59 and 62 are semicircular to correspond to the upper ends of the opening 86 and the aperture 29, respectively, with which they are substantially concentric.

Within the housing I3, below the roll assembly 55, is a drum assembly 81that includes a casting that includes a body 88 in the form of along horizontal bar that extends transversely through the housing 13. On the left-hand end of the body 98 is an integral upstanding flat plate 89 secured by screws 99 to the housing side member 19 with its upper end flush with the bottom of the aperture 29 therein. A pair of axially aligned bearings 9| and 92 are formed, the former with the plate 89 and the latter on the other end portion of the body 88; On the upper side of the body 88, at its transverse center, is a reinforcing rib 93, th ends of which are integral with the plate 89and bearings 9i and 92.

A tubular rock shaft 99 of a relatively large diameter, is mounted in the bearings 9| and 92. Extending through the tubular shaft 94 is a shaft 96 journaled in bushings 91 secured in the end portions of the tubular shaft 94. The shaft 96 extends obliquely substantially in a horizontal plane, through the tubular shaft 94 and the end portions thereof are journaled in the bushings 91 eccentric to the axis thereof and on opposite sides of said axis, see Fig. 12. The shaft 94 extends outwardly of the bushings 91 and the-cams 66 and 61 are rigidly secured thereto. Obviously, by turning the shaft 96 in the bushings 91, one of the cams 66 and 61 will be raised and the other lowered and thereby move the cradle 59 and tilt the roll I6 on its longitudinal axis in a vertical plane. Each cam 66 and 67 is a vertically disposed flat plate, the top of which is substantially semicircular. The axes of the cams 666'I are rearwardly offset from the axis of the shaft 96 to which they are secured. The rollers 64 and 65 rest on the cams 66-6'I substantially over their axes. A depending bearing plate 98 is detachably secured to the right-hand end of the body 98 by screws 99. A drum I00, of a diameter considerably larger than that of the roll I6, has on its ends trunnions IOI journaled in the housing side member I1 and the bearing plate 98. The roll I6 and the drum I each has a resilient sleeve on its periphery of rubber, felt or other suitable cushioning material. A wide endless belt a by which it may be turned, extends into the compartment 30 through a hole I06 in the front member 3|. The screw rod I04 also extends through a bearing I01 therefor and has threaded engagement with a nut-acting member I08 that extends between and is swivelled to a pair of depending plates I 09 secured to the cam 66 on opposite sides thereof. The bearing I0! is mounted in the housing side member I1 and the fram side member 28 to turn about a horizontal axis. A coiled spring IIO encircling the screw rod I04 is held compressed between the bearing I01 and a collar II I on said screw rod and yieldingly holds the cams 66 and B! where adjusted. The position of the cams 66-61 in the drawings supports the roll assembly 56 in a lowered position to put slack in the abrading belt I03. To tighten the abrading belt I 03, the roll assembly 56 is lifted by manipulating the screw rod I04 to swing the cam 61 upwardly and forwardly. This movement of the cam 61 imparts a like movement to the cam 66 by means of the shaft 96 to which both cams 66-6'I are rigidly connected.

It may be here stated that by removing the abrading belt I03 from the roll I6 and the drum I00 and the screws 43 from the hubs 44, the motor bed 39 may be lifted with the motor 4'! thereon to clear the frame side member 28 andthen moved outwardly to withdraw the entire roll assembly 56 from the housing I3 through the aperture 20 and openings 86, without disturbing the belts 19 or any other of the assembly parts.

The improved sanding machine is moved and guided by a handle I I2 in the form of a tube secured at its inner end in a hollow T-casting II3 turnably mounted on a hinge rod I I4 that extends through aligned holes in the head of said casting and a pair of upstanding bearings I I 5 between which the casting II3 extends. The bearings II5 have outturned flanges II6 which, together with said bearings, rest on the top of the housing I3 and are secured thereto by screws I II. On the outer end portions of the hinge rod II4 are washers H8 and cap nuts II9. A cast head I is secured to the outer end of the handle I I2.

On the right-hand side of the head I20 is a hand hold I2I, on the under side thereof is a depending hand grip I22 and'on the right-hand side of said head is a turnable hand grip I23 axially aligned with the hand hold I2I. The hand grip I23 is secured at its inner end to a long pin I24 turnably mounted in the head I20 and the hand hold I2I In case the abrading belt I03 drifts on the roll I6 and drum I00, said roll may be tilted axially in a vertical plane to return said belt to its normal position by the following manually operated connections: a depending lever I25 is secured to the hand grip I23 at its inner end to be operated thereby. This lever I25 is provided on its outer side with an integral thumb-piece I26. A second lever I2! is pivoted on the left-hand end portion of the hinge rod II4 between a washer I28 that impinges the adjacent bearing H5 and the respective washer I I8. This second lever I21 has on its inner side a wide reinforcing rib I29 that extends centrally and longitudinally thereof and provided at its longitudinal center and in the plane thereof with a boss I30. A long connecting link I3I is pivoted at one end to the outer end of the lever I25 and pivoted at its other end to the boss I30. A depending lever I32 for turning the tubular shaft 94 has on one end a collar I 33 fitted on the ends of said shaft in the housing I3 and secured thereto in difierent relative circumferential adjustments by set screws I34. Swiveled on the outer end portion of the lever I32 is a guide I35. A long rod I36 is pivotally attached at one end to the outer end of the lever I32 and its other end portion extends through a hole in the guide I and secured thereto, when endwise adjusted therein to vary its operative length, by a set screw I31.

Formed in the top member I4 and the side member I? of "the housing I3 is a sight opening I38 through which the operator of the sanding machine may watch the abrading belt I03 to see that it does not drift on the drum I06. In case the abrading belt I03 drifts on the drum I09, it is only necessary for the operator to manipulate the lever I25 to tilt the roll I6 in the proper direction to return the abrading belt I03 to its correct position on the drum I90.

Dust cut from a floor being sanded by the machine is thrown by the abrading belt I03 into the dust scoop chamber 2I Where it is drawn through the passageway 25 into the fan housing -I39 by a suction fan I40 in said housing. This suction fan I40 is operated directly by an electric motor I4I secured to the housing I39. From the housing I39, the dust is delivered by the suction fan I40 into a long flexible metal conduit I42. The conduit I42 is connected just above the fan housing I39 to the back member I6 of the housing I3 by a two-part clamp I43. From the clamp I43, the conduit I42 extends upwardly to a point just above the motor 4'! and then horizontally rearward and into a dust-collecting bag I44. This dust bag I44 has a neck portion I45 through which the conduit I42 extends and is secured thereto by a tied piece of tape I46. The dust bag I44 also has a looped piece of tape I4'I placed over the hand hold I2I and supports said dust bag therefrom. Formed in the upper rear portion of the dust bag I44 is a dust discharge opening I48 through which said bag is emptied. This opening I48 is normally closed by any one of the well known separable fasteners I49 including slide operated interlocking members. A bafile IS, in the form of a horizontal bar, is secured to the rear member I6 with the housingI 3.; This asespeo bafiie'lfi. substantially fillsithe space between the housing rear member. lE and the upper run of the abrading belt I03 to prevent dust in the scoop chamber 2! fromfollowing said belt.

An electric bulb I53, for illuminating the work in advance of the sanding machine, is mounted in a socket 151 secured to the front member l5 of the housing I3. Also secured to the front member is a hood L32 for the electric light bulb I50. In the front member i5 is a glass window 153 directly back of the electric light bulb I through which the interior of the housing I3 is illuminated. The electric light wiring for the electric motors d! and Ml and the electric light bulb is indicated as an entirety by the numeral 154 with the exception. of the switch I in the head lZB of the handle ll2iand the coupling member list-applicable to an extension cord, not shown, leading from any suitable outlet. The handle H2, the casting H3 and the head lZG afford a conduit for certain parts of the wiring From a broad viewpoint, the housing l3 may be considered to be a main frame and the frame 25 a secondary frame.

From what has been said, it will be understood that the floor sanding machine described is capable of modifications as to details of construction and arrangement within the scope of the invention herein described and claimed.

What I claim is:

1. In a floor sanding machine, a frame, a lower drum journaled in the frame, a cam assembly in the frame including a pair of eccentric cams connected for common movement in vertical planes, means for operating the cams, an upper driven roll assembly in the frame including a cradle supported on the cams, a driven roll journaled in the cradle, an endless abrading belt arranged to run under the drum and over the driven roll, said drum supporting the frame from the floor and pressing the abrading belt thereon, a motor, and driving connections from the motor to the driven roll.

2. In a floor sanding machine, a frame, a lower drum journaled in the frame, a cam assembly in the frame including bearings, a tubular rock shaft journaled in the bearings, an inner shaft journaled in the rock shaft and extending outwardly thereof, the end portions of the inner shaft bei ing eccentric to the axis of the rock shaft and on opposite sides thereof substantially in a horizontal plane, an eccentric cam on each end of the inner shaft, means for turning the rock shaft to simultaneously raise or lower the cams, other means for turning the inner shaft relative to the rock shaft to raise one cam and lower the other, an upper driven roll assembly including a cradle supported on the cams, a driven roll journaled on the cradle, an endless abrading belt arranged to run under the drum and over the driven roll, said drum supporting the frame from the floor and pressing the abrading belt thereon, a motor, and drivingconnections from the motor to the driven roll.

3. The structure defined in claim 2 in which the means for turning the inner shaft relative to the rock shaft comprises a long screw rod, a swiveled bearing in which the screw rod is mounted for compound turning and endwise sliding movement, at swiveled nut-acting member attached to one of the cams with which the screw rod has threaded engagement, a collar on the screw rod between the bearing and nut-acting member, and a coiled spring encircling the screw rod and comcradle is supported on the same side of the frame as the bearings, said frame having in its other side an aperture through which the abrading belt may be removed edgewise from the drum and the upper roll and from the frame.

7. In a floor sanding machine, a mainframe, asecondary frame secured to the main frame and having floor wheels, a lower drumjournaled' in the main frame and supporting the same from the floor, a motor bed removably hinged'to the secondary frame for movement in a vertical plane and having an extension mount at one side of the main frame, an upper driven roll assembly including a cradle, extending transversely through the main frame and attached at one end,

to the mount extension, means supporting. the

mount extension and the cradle at its outer end portion and operable to simultaneously raise or lower said mount extension and the cradle, a driven roll journaled on the cradle,.an endless abrading belt arranged to run under the drum and over the driven roll, said drumsupporting the main frame on the floor and pressing the abrading belt thereon, a motor on the motor bed, and driving connections from the motor to the driven roll.

8. The structure defined in claim 7 in which the cradle is hinged to the mount extension for vertical movement.

9.- In a floor sanding machine, a main frame,

a secondary frame secured to the main, frameand having floor wheels, a lower drum journaled in the main frame and supporting the same, from the floor, a motor bed removably hinged to the secondary frame for movement in a vertical plane and having a mount extension at one side of the main frame, an upper driven roll assembly including a cradle extending transversely through the main frame and hinged at one end for movement in a vertical plane, a pair of cams, a roller on the mount extension resting on one cam, a second roller on the outer end portion of the cradle and resting on the other cam, means for operating the cams to simultaneously raise the mount extension and lower the cradle on opposite sides of the main frame and vice versa, other means for operating the cams to impart reverse raising and lowering movements to said mount extension and cradle, an endless abrading belt arranged to run under the drum and over the driven roll, said drum supporting the main frame from the floor and pressing the abrading belt thereon, a motor on the motor bed, and driving connections from the motor to the driven roll.

10. In a floor sanding machine, a main frame having side members, an idle drum and a pair of floorv wheels journaled on the frame and supporting the same with lower edges of the side ondary frame in the main frame and hinged thereto at its rear end for raising and lowering movements, movable means on the main frame supporting the secondary frame at its front end, a cradle fixed to the front end portion of the secondary frame, a driven roll journaled in the cradle, an endless abrasive belt arranged to run under the drum and over the driven roll, means for driving the roll, means for operating the movable means to raise the secondary frame and tighten the abrasive belt, and vice versa.

11. In a floor sanding machine, a main frame, an idle drum journaled on the main frame, a horizontally disposed secondary frame hinged at its rear end to the main frame to move about a horizontal axis and with its front end portion above the drum, a roll journaled on the front end portion of the secondary frame, adjustable members on the main frame supporting the secondary frame, an endless abrading belt arranged to run under the drum and over the roll, means for adjusting the adjustable members to raise the secondary frame to tighten the belt, and vice versa, a motor on the secondary frame, and driv-' ing connections from the motor to the roll.

12. In a floor sanding machine, a main frame, an idle drum journaled on the main frame, a horizontally disposed secondary frame hinged at its rear end to the main frame to move about a horizontal axis and with its front end portion above the drum, a roll journaled on the front end portion of the secondary frame, a pair of adjustable members on the main frame supporting the secondary frame, an endless abrading belt arranged to run under the drum and over the roll, means for imparting one adjustment to the adjustable members to raise the secondary frame to tighten the belt, and vice versa, a second means for imparting a second adjustment to the adjustable members for tilting the roll relative to the axis of the drum, a motor on the secondary frame, and driving connections from the motor to the roll.

13. In a floor sanding machine, a main frame, an idle drum journaled on the main frame, a horizontally disposed secondary frame hinged at its rear end to move about a horizontal axis and with its front end portion above the drum, a cradle extending transversely of the secondary frame and hinged thereto at one end to turn about a horizontal axis, a pair of adjustable members on the main frame, a pair of rollers journaled on the cradle and resting on the adjustable members and supporting the secondary frame therefrom, the roller on the opposite end of the cradle from its hinged end being adjustable to tilt the cradle, a roll journaled in the cradle, an endless abrading belt arranged to run under the drum and over the roll, means for simultaneously imparting one adjustment to the adjustable means to raise the cradle and tighten the belt, and vice versa, a second means for simultaneously imparting a second adjustment to the adjustable means to tilt the cradle relative to the axis of the drum, a motor on the secondary frame, and driving connections from the motor to the end of the roll at the hinged end of the cradle.

14. In a floor sanding machine, a frame, an idle drum journaled on the frame, a cradle, means mounting the cradle on the frame for raising and lowering movements over the drum, a pair of adjustable members on the frame supporting the cradle, an endless abrading belt arranged to run under the drum and over the roll, means for simultaneously imparting one adjustment to the adjustable means to raise the cradle and tighten the belt, and vice versa, a second means for simultaneously imparting a second adjustment to the adjustable means to tilt the cradle relative to the axis of the drum, a motor on the cradle mounting means, and driving connections from the motor to the roll.

15. The structure defined in claim 14, further including a resilient sleeve on the drum held compressed by the tightening of the belt.

JOSEPH E. SWALINKAVICH, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,108,176 Hormel Aug. 25, 1914 1,356,338 Clarke Oct. 19, 1920 2,222,966 Williams NOV. 26, 1940 2,477,358 Adams July 26, 1949 FOREIGN PATENTS Number Country Date 785,881 France May 27, 1935 

